Quelle  phy-bcm-ns2-usbdrd.c   Sprache: C

// SPDX-License-Identifier: GPL-2.0-only
// Copyright (C) 2017 Broadcom

#include <linux/delay.h>
#include <linux/extcon-provider.h>
#include <linux/gpio.h>
#include <linux/gpio/consumer.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/iopoll.h>
#include <linux/irq.h>
#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/phy/phy.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/slab.h>
#include <linux/workqueue.h>

#define ICFG_DRD_AFE  0x0
#define ICFG_MISC_STAT  0x18
#define ICFG_DRD_P0CTL  0x1C
#define ICFG_STRAP_CTRL  0x20
#define ICFG_FSM_CTRL  0x24

#define ICFG_DEV_BIT  BIT(2)
#define IDM_RST_BIT  BIT(0)
#define AFE_CORERDY_VDDC BIT(18)
#define PHY_PLL_RESETB  BIT(15)
#define PHY_RESETB  BIT(14)
#define PHY_PLL_LOCK  BIT(0)

#define DRD_DEV_MODE  BIT(20)
#define OHCI_OVRCUR_POL  BIT(11)
#define ICFG_OFF_MODE  BIT(6)
#define PLL_LOCK_RETRY  1000

#define EVT_DEVICE  0
#define EVT_HOST  1

#define DRD_HOST_MODE  (BIT(2) | BIT(3))
#define DRD_DEVICE_MODE  (BIT(4) | BIT(5))
#define DRD_HOST_VAL  0x803
#define DRD_DEV_VAL  0x807
#define GPIO_DELAY  20

struct ns2_phy_data;
struct ns2_phy_driver {
 void __iomem *icfgdrd_regs;
 void __iomem *idmdrd_rst_ctrl;
 void __iomem *crmu_usb2_ctrl;
 void __iomem *usb2h_strap_reg;
 struct ns2_phy_data *data;
 struct extcon_dev *edev;
 struct gpio_desc *vbus_gpiod;
 struct gpio_desc *id_gpiod;
 int id_irq;
 int vbus_irq;
 unsigned long debounce_jiffies;
 struct delayed_work wq_extcon;
};

struct ns2_phy_data {
 struct ns2_phy_driver *driver;
 struct phy *phy;
 int new_state;
};

static const unsigned int usb_extcon_cable[] = {
 EXTCON_USB,
 EXTCON_USB_HOST,
 EXTCON_NONE,
};

static inline int pll_lock_stat(u32 usb_reg, int reg_mask,
    struct ns2_phy_driver *driver)
{
 u32 val;

 return readl_poll_timeout_atomic(driver->icfgdrd_regs + usb_reg,
      val, (val & reg_mask), 1,
      PLL_LOCK_RETRY);
}

static int ns2_drd_phy_init(struct phy *phy)
{
 struct ns2_phy_data *data = phy_get_drvdata(phy);
 struct ns2_phy_driver *driver = data->driver;
 u32 val;

 val = readl(driver->icfgdrd_regs + ICFG_FSM_CTRL);

 if (data->new_state == EVT_HOST) {
  val &= ~DRD_DEVICE_MODE;
  val |= DRD_HOST_MODE;
 } else {
  val &= ~DRD_HOST_MODE;
  val |= DRD_DEVICE_MODE;
 }
 writel(val, driver->icfgdrd_regs + ICFG_FSM_CTRL);

 return 0;
}

static int ns2_drd_phy_poweroff(struct phy *phy)
{
 struct ns2_phy_data *data = phy_get_drvdata(phy);
 struct ns2_phy_driver *driver = data->driver;
 u32 val;

 val = readl(driver->crmu_usb2_ctrl);
 val &= ~AFE_CORERDY_VDDC;
 writel(val, driver->crmu_usb2_ctrl);

 val = readl(driver->crmu_usb2_ctrl);
 val &= ~DRD_DEV_MODE;
 writel(val, driver->crmu_usb2_ctrl);

 /* Disable Host and Device Mode */
 val = readl(driver->icfgdrd_regs + ICFG_FSM_CTRL);
 val &= ~(DRD_HOST_MODE | DRD_DEVICE_MODE | ICFG_OFF_MODE);
 writel(val, driver->icfgdrd_regs + ICFG_FSM_CTRL);

 return 0;
}

static int ns2_drd_phy_poweron(struct phy *phy)
{
 struct ns2_phy_data *data = phy_get_drvdata(phy);
 struct ns2_phy_driver *driver = data->driver;
 u32 extcon_event = data->new_state;
 int ret;
 u32 val;

 if (extcon_event == EVT_DEVICE) {
  writel(DRD_DEV_VAL, driver->icfgdrd_regs + ICFG_DRD_P0CTL);

  val = readl(driver->idmdrd_rst_ctrl);
  val &= ~IDM_RST_BIT;
  writel(val, driver->idmdrd_rst_ctrl);

  val = readl(driver->crmu_usb2_ctrl);
  val |= (AFE_CORERDY_VDDC | DRD_DEV_MODE);
  writel(val, driver->crmu_usb2_ctrl);

  /* Bring PHY and PHY_PLL out of Reset */
  val = readl(driver->crmu_usb2_ctrl);
  val |= (PHY_PLL_RESETB | PHY_RESETB);
  writel(val, driver->crmu_usb2_ctrl);

  ret = pll_lock_stat(ICFG_MISC_STAT, PHY_PLL_LOCK, driver);
  if (ret < 0) {
   dev_err(&phy->dev, "Phy PLL lock failed\n");
   return ret;
  }
 } else {
  writel(DRD_HOST_VAL, driver->icfgdrd_regs + ICFG_DRD_P0CTL);

  val = readl(driver->crmu_usb2_ctrl);
  val |= AFE_CORERDY_VDDC;
  writel(val, driver->crmu_usb2_ctrl);

  ret = pll_lock_stat(ICFG_MISC_STAT, PHY_PLL_LOCK, driver);
  if (ret < 0) {
   dev_err(&phy->dev, "Phy PLL lock failed\n");
   return ret;
  }

  val = readl(driver->idmdrd_rst_ctrl);
  val &= ~IDM_RST_BIT;
  writel(val, driver->idmdrd_rst_ctrl);

  /* port over current Polarity */
  val = readl(driver->usb2h_strap_reg);
  val |= OHCI_OVRCUR_POL;
  writel(val, driver->usb2h_strap_reg);
 }

 return 0;
}

static void connect_change(struct ns2_phy_driver *driver)
{
 u32 extcon_event;
 u32 val;

 extcon_event = driver->data->new_state;
 val = readl(driver->icfgdrd_regs + ICFG_FSM_CTRL);

 switch (extcon_event) {
 case EVT_DEVICE:
  val &= ~(DRD_HOST_MODE | DRD_DEVICE_MODE);
  writel(val, driver->icfgdrd_regs + ICFG_FSM_CTRL);

  val = (val & ~DRD_HOST_MODE) | DRD_DEVICE_MODE;
  writel(val, driver->icfgdrd_regs + ICFG_FSM_CTRL);

  val = readl(driver->icfgdrd_regs + ICFG_DRD_P0CTL);
  val |= ICFG_DEV_BIT;
  writel(val, driver->icfgdrd_regs + ICFG_DRD_P0CTL);
  break;

 case EVT_HOST:
  val &= ~(DRD_HOST_MODE | DRD_DEVICE_MODE);
  writel(val, driver->icfgdrd_regs + ICFG_FSM_CTRL);

  val = (val & ~DRD_DEVICE_MODE) | DRD_HOST_MODE;
  writel(val, driver->icfgdrd_regs + ICFG_FSM_CTRL);

  val = readl(driver->usb2h_strap_reg);
  val |= OHCI_OVRCUR_POL;
  writel(val, driver->usb2h_strap_reg);

  val = readl(driver->icfgdrd_regs + ICFG_DRD_P0CTL);
  val &= ~ICFG_DEV_BIT;
  writel(val, driver->icfgdrd_regs + ICFG_DRD_P0CTL);
  break;

 default:
  pr_err("Invalid extcon event\n");
  break;
 }
}

static void extcon_work(struct work_struct *work)
{
 struct ns2_phy_driver *driver;
 int vbus;
 int id;

 driver  = container_of(to_delayed_work(work),
          struct ns2_phy_driver, wq_extcon);

 id = gpiod_get_value_cansleep(driver->id_gpiod);
 vbus = gpiod_get_value_cansleep(driver->vbus_gpiod);

 if (!id && vbus) { /* Host connected */
  extcon_set_state_sync(driver->edev, EXTCON_USB_HOST, true);
  pr_debug("Host cable connected\n");
  driver->data->new_state = EVT_HOST;
  connect_change(driver);
 } else if (id && !vbus) { /* Disconnected */
  extcon_set_state_sync(driver->edev, EXTCON_USB_HOST, false);
  extcon_set_state_sync(driver->edev, EXTCON_USB, false);
  pr_debug("Cable disconnected\n");
 } else if (id && vbus) { /* Device connected */
  extcon_set_state_sync(driver->edev, EXTCON_USB, true);
  pr_debug("Device cable connected\n");
  driver->data->new_state = EVT_DEVICE;
  connect_change(driver);
 }
}

static irqreturn_t gpio_irq_handler(int irq, void *dev_id)
{
 struct ns2_phy_driver *driver = dev_id;

 queue_delayed_work(system_power_efficient_wq, &driver->wq_extcon,
      driver->debounce_jiffies);

 return IRQ_HANDLED;
}

static const struct phy_ops ops = {
 .init  = ns2_drd_phy_init,
 .power_on = ns2_drd_phy_poweron,
 .power_off = ns2_drd_phy_poweroff,
 .owner  = THIS_MODULE,
};

static const struct of_device_id ns2_drd_phy_dt_ids[] = {
 { .compatible = "brcm,ns2-drd-phy", },
 { }
};
MODULE_DEVICE_TABLE(of, ns2_drd_phy_dt_ids);

static int ns2_drd_phy_probe(struct platform_device *pdev)
{
 struct phy_provider *phy_provider;
 struct device *dev = &pdev->dev;
 struct ns2_phy_driver *driver;
 struct ns2_phy_data *data;
 int ret;
 u32 val;

 driver = devm_kzalloc(dev, sizeof(struct ns2_phy_driver),
         GFP_KERNEL);
 if (!driver)
  return -ENOMEM;

 driver->data = devm_kzalloc(dev, sizeof(struct ns2_phy_data),
      GFP_KERNEL);
 if (!driver->data)
  return -ENOMEM;

 driver->icfgdrd_regs = devm_platform_ioremap_resource_byname(pdev, "icfg");
 if (IS_ERR(driver->icfgdrd_regs))
  return PTR_ERR(driver->icfgdrd_regs);

 driver->idmdrd_rst_ctrl = devm_platform_ioremap_resource_byname(pdev, "rst-ctrl");
 if (IS_ERR(driver->idmdrd_rst_ctrl))
  return PTR_ERR(driver->idmdrd_rst_ctrl);

 driver->crmu_usb2_ctrl = devm_platform_ioremap_resource_byname(pdev, "crmu-ctrl");
 if (IS_ERR(driver->crmu_usb2_ctrl))
  return PTR_ERR(driver->crmu_usb2_ctrl);

 driver->usb2h_strap_reg = devm_platform_ioremap_resource_byname(pdev, "usb2-strap");
 if (IS_ERR(driver->usb2h_strap_reg))
  return PTR_ERR(driver->usb2h_strap_reg);

  /* create extcon */
 driver->id_gpiod = devm_gpiod_get(&pdev->dev, "id", GPIOD_IN);
 if (IS_ERR(driver->id_gpiod)) {
  dev_err(dev, "failed to get ID GPIO\n");
  return PTR_ERR(driver->id_gpiod);
 }
 driver->vbus_gpiod = devm_gpiod_get(&pdev->dev, "vbus", GPIOD_IN);
 if (IS_ERR(driver->vbus_gpiod)) {
  dev_err(dev, "failed to get VBUS GPIO\n");
  return PTR_ERR(driver->vbus_gpiod);
 }

 driver->edev = devm_extcon_dev_allocate(dev, usb_extcon_cable);
 if (IS_ERR(driver->edev)) {
  dev_err(dev, "failed to allocate extcon device\n");
  return -ENOMEM;
 }

 ret = devm_extcon_dev_register(dev, driver->edev);
 if (ret < 0) {
  dev_err(dev, "failed to register extcon device\n");
  return ret;
 }

 ret = gpiod_set_debounce(driver->id_gpiod, GPIO_DELAY * 1000);
 if (ret < 0)
  driver->debounce_jiffies = msecs_to_jiffies(GPIO_DELAY);

 INIT_DELAYED_WORK(&driver->wq_extcon, extcon_work);

 driver->id_irq = gpiod_to_irq(driver->id_gpiod);
 if (driver->id_irq < 0) {
  dev_err(dev, "failed to get ID IRQ\n");
  return driver->id_irq;
 }

 driver->vbus_irq = gpiod_to_irq(driver->vbus_gpiod);
 if (driver->vbus_irq < 0) {
  dev_err(dev, "failed to get ID IRQ\n");
  return driver->vbus_irq;
 }

 ret = devm_request_irq(dev, driver->id_irq, gpio_irq_handler,
          IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
          "usb_id", driver);
 if (ret < 0) {
  dev_err(dev, "failed to request handler for ID IRQ\n");
  return ret;
 }

 ret = devm_request_irq(dev, driver->vbus_irq, gpio_irq_handler,
          IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
          "usb_vbus", driver);
 if (ret < 0) {
  dev_err(dev, "failed to request handler for VBUS IRQ\n");
  return ret;
 }

 dev_set_drvdata(dev, driver);

 /* Shutdown all ports. They can be powered up as required */
 val = readl(driver->crmu_usb2_ctrl);
 val &= ~(AFE_CORERDY_VDDC | PHY_RESETB);
 writel(val, driver->crmu_usb2_ctrl);

 data = driver->data;
 data->phy = devm_phy_create(dev, dev->of_node, &ops);
 if (IS_ERR(data->phy)) {
  dev_err(dev, "Failed to create usb drd phy\n");
  return PTR_ERR(data->phy);
 }

 data->driver = driver;
 phy_set_drvdata(data->phy, data);

 phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
 if (IS_ERR(phy_provider)) {
  dev_err(dev, "Failed to register as phy provider\n");
  return PTR_ERR(phy_provider);
 }

 platform_set_drvdata(pdev, driver);

 queue_delayed_work(system_power_efficient_wq, &driver->wq_extcon,
      driver->debounce_jiffies);

 return 0;
}

static struct platform_driver ns2_drd_phy_driver = {
 .probe = ns2_drd_phy_probe,
 .driver = {
  .name = "bcm-ns2-usbphy",
  .of_match_table = of_match_ptr(ns2_drd_phy_dt_ids),
 },
};
module_platform_driver(ns2_drd_phy_driver);

MODULE_ALIAS("platform:bcm-ns2-drd-phy");
MODULE_AUTHOR("Broadcom");
MODULE_DESCRIPTION("Broadcom NS2 USB2 PHY driver");
MODULE_LICENSE("GPL v2");